Multi-format output device, control method for multi-format output device

ABSTRACT

A multi-format output device includes decoders to decode first encoded data and second encoded data to generate a first video data having a first-type format with first caption data also having the first-type format, and second video data having a second-type format with second caption data also having the second-type format. A conversion unit converts video data of one format type into video data having another format-type. A buffer holds the first video data by the period of time needed for the video data conversion processing. A caption conversion unit delays the caption data for the video data conversion processing time and also converts the caption data of one format type to another format type. A multiplexer outputs the first video data with the first caption data followed by the converted video data with the third caption data having the first-type format.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a division of U.S. patent application Ser. No.14/026,570, filed on Sep. 13, 2013, which is based upon and claims thebenefit of priority from Japanese Patent Application No. 2012-203347,filed Sep. 14, 2012, the entire contents of each of which areincorporated herein by reference.

FIELD

Embodiments described herein relate to a multi-format output device anda control method for multi-format output device.

BACKGROUND

When encoded data of the SD (Standard Definition) format are supplied toa multi-format output device, the encoded data are decoded into SD videodata, and the decoded data are then up-converted into HD (HighDefinition) video data. In this way, the multi-format output deviceintegrates SD video data with HD video data, which is obtained bydecoding encoded HD data. The multi-format output device outputs the HDvideo data when the output format is HD and down converts the HD videodata and outputs the down converted data as SD video data when theoutput format is SD.

Also, the multi-format output device converts SD caption data added tothe encoded SD data into HD caption data for the up-conversion of the SDvideo data into the HD video data. In this way, the multi-format outputdevice integrates the SD caption data with the HD caption data. Themulti-format output device multiplexes the HD caption data with the HDvideo data when the output format is HD, and converts the HD captiondata to the SD caption data and multiplexes them with the SD video datawhen the output format is SD.

However, in the case of outputting the encoded SD data in the SD format,a multi-format output device may have to perform down-conversion afterfirst up-converting the SD video data. As a result, the image quality ofthe SD video data may deteriorate. Also, in the case of outputting theencoded SD data in the SD format, the multi-format output device mayhave to convert the caption data into SD caption data after convertingthem into HD caption data. As a result, the processing becomescomplicated.

As described above, since the related multi-format output device carriesout conversion twice when outputting SD video data or SD caption data inthe SD format, the image quality of the SD video data may deteriorate,and the processing becomes complicated.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating the functional configuration of abroadcasting station, wherein a video server equipped with amulti-format output device according to an embodiment of the presentdisclosure may be incorporated.

FIG. 2 depicts a multi-format output device according to an embodiment.

FIG. 3 is a flow chart illustrating the processing of the control unitin an embodiment of a multi-format output device when HD video data andSD video data are output.

FIG. 4 is a diagram related to the process of outputting the HD videodata according to an embodiment.

FIG. 5 is a diagram related to the process of outputting the SD videodata according to an embodiment.

FIG. 6 is depicts a multi-format output device according to anembodiment.

DETAILED DESCRIPTION

In general, an embodiment will be explained with reference to thedrawings. As an example embodiment, a multi-format output device and acontrol method for a multi-format output device that can output an HDimage with HD captions and/or an SD image with SD captions withoutcomplicated processing and without deterioration in image quality isdescribed.

According to an embodiment, a multi-format output device includes afirst decoder configured to receive a first-type encoded data and decodethe first-type encoded data to generate a first video data having afirst-type format (e.g., High-Definition or Standard Definition) and afirst caption data having the first-type format, and a second decoderconfigured to receive a second-type encoded data and decode thesecond-type encoded data to generate a second video data having asecond-type format (e.g., High-Definition or Standard Definition) and asecond caption data having the second-type format. A conversion unitconfigured to convert the second video data to generate a third videodata having the first-type format is included. The conversion unit mayalso be configured to convert first video data to generate a fourthvideo data having the second-type format. A first buffer is configuredto store the first-type encoded data or the first video data for atleast a first period of time substantially equivalent to a period oftime required for the conversion unit to generate the third video data.A caption conversion unit is configured to delay output of the firstcaption data for at least the first period of time and generate a thirdcaption data by converting the second caption data to the first-typeformat. A first multiplexing unit is configured to output the firstvideo data with the first caption data followed by the third video datawith the third caption data.

According to another embodiment, a multi-format output device includes areceiving circuit, first and second decoders, a conversion unit, abuffer, a caption conversion unit, a multiplexing unit, and an outputunit. The receiving circuit receives a first encoded data and a secondencoded data in a video format different from the first encoded data andseparates and outputs the first encoded data and the second encodeddata. The first decoder decodes the first encoded data supplied from thereceiving circuit to generate the first video data and the first captiondata. The second decoder decodes the second encoded data supplied fromthe receiving circuit to generate the second video data and the secondcaption data. The conversion unit converts the first video datagenerated by the first decoder into a third video data conforming to thesame definition as the second video data. The buffer holds the secondvideo data generated by the second decoder and delays the video data bythe period of time needed for the conversion processing in theconversion unit. The caption conversion unit delays the first and secondcaption data by the period of time and converts the first caption datainto a third caption data conforming to the definition. The multiplexingunit multiplexes the third caption data with the third video data andmultiplexes the delayed second caption data with the delayed secondvideo data. The output unit outputs the second video data multiplexedwith the second caption data when outputting the third video datamultiplexed with the third caption data.

FIG. 1 is a diagram illustrating an example of the functionalconfiguration of a broadcasting station, wherein a video server 100equipped with a multi-format output device 10 disclosed in thisembodiment is set up. As shown in FIG. 1, a video server 100, anautomatic program sending controller (APC) 200, and an in-station clock201 are set in a broadcasting station. The APC 200 outputs aninstruction to the video server 100 to reproduce the program materialsthat is to be reproduced according to the time shown in the in-stationclock 201 when the in-station clock 201 reaches the time indicated in aplay list formed based on the broadcasting schedule.

The video server 100 includes a multi-format output device 10, a storagedevice 20, and a reproducing controller 30. The multi-format outputdevice 10 is connected to the storage device 20 by, for example, anEthernet connection.

Instructions are sent from APC 200 to the reproducing controller 30 tocontrol the multi-format output device 10 to output the designatedprogram material to a prescribed output destination.

The reproducing controller 30 controls the multi-format output device 10to read out encoded SD data and/or the encoded HD data stored in thestorage device 20. The constituent elements of the multi-format outputdevice are controlled appropriately to output the program material tothe designated output destination.

In this embodiment, the encoded SD data are obtained by encoding the SDvideo data and SD caption data added to the SD video data. A presetencoding method is used in this example to generate the encoded SD data.The encoded HD data are obtained by encoding the HD video data and theHD caption data added to the HD video data using. A preset encodingmethod is used in this example to generate the encoded HD data.

FIG. 2 is a block diagram illustrating the functional configuration ofthe multi-format output device 10 disclosed in this embodiment. Themulti-format output device 10 shown in FIG. 2 includes a receivingcircuit 11, a first decoder 12-1, a second decoder 12-2, a first buffer13-1, a second buffer 13-2, a caption converter 14, a first switchingunit 15-1, a second switching unit 15-2, a converter 16, a firstmultiplexer 17-1, a second multiplexer 17-2, a first output unit 18-1, asecond output unit 18-2, and a controller 19.

The receiving circuit 11 receives encoded data supplied from the storagedevice 20 and then selectively outputs the received encoded data to thefirst or second decoder 12-1, 12-2. When the encoded data having asingle format are supplied continuously, the receiving circuit 11outputs the supplied encoded data to the same decoder. When the encodeddata having different formats are supplied simultaneously, the receivingcircuit 11 outputs the different encoded data to different decoders.

For example, when the encoded SD data are supplied from the receivingcircuit 11, the first decoder 12-1 decodes the encoded SD data togenerate SD video data and the caption data for SD. When the encoded HDdata are supplied from the receiving circuit 11, the first decoder 12-1decodes the encoded HD data to generate HD video data and the captiondata for HD.

The first decoder 12-1 outputs the SD video data or HD video datagenerated by the decoding processing to the first buffer 13-1 andoutputs the SD caption data or the HD caption data to the captionconverter 14. Similar to the first decoder 12-1, the second decoder 12-2decodes the encoded SD data or the encoded HD data supplied from thereceiving circuit 11 to generate the SD video data or the HD video dataand the caption data for SD or the caption data for HD. The seconddecoder 12-2 outputs the SD video data or HD video data generated by thedecoding processing to the second buffer 13-2 and outputs the SD captiondata or the HD caption data to the caption converter 14.

The SD video data or HD video data are supplied from the first decoder12-1 to the first buffer 13-1. The first buffer 13-1 outputs thesupplied SD video data or HD video data to the first and secondswitching units 15-1, 15-2 according to the first read control from thecontroller 19. Based on the first read control, the first buffer 13-1delays the output of the SD video data or HD video data to the firstswitching unit 15-1 by as much as the time needed for the conversionprocessing performed by the converter 16 compared to the output time ofthe SD video data or HD video data to the second switching unit 15-2.

The SD video data or HD video data are supplied from the second decoder12-2 to the second buffer 13-2. The second buffer 13-2 outputs thesupplied SD video data or HD video data to the first and secondswitching units 15-1, 15-2 according to the second read control from thecontroller 19. Based on the second read control, the second buffer 13-2delays the output of the SD video data or HD video data to the firstswitching unit 15-1 by as much as the time needed for the conversionprocessing performed by the converter 16 compared to the output time ofthe SD video data or HD video data to the second switching unit 15-2.

The caption converter 14 receives the caption data for SD or captiondata for HD supplied from the first decoder 12-1 and receives thecaption data for SD or caption data for HD supplied from the seconddecoder 12-2.

According to a caption control sent from the controller 19, the captionconverter 14 delays outputting of the received SD caption data by asmuch as the time needed for the conversion processing performed by theconverter 16, and then outputs the caption data to the first multiplexer17-1.

Also, according to the caption control sent from the controller 19, thecaption converter 14 converts received SD caption data into HD captiondata, delays outputting of the caption data by as much as the timeneeded for the conversion processing performed by the converter 16, andthen outputs the caption data to the second multiplexer 17-2.

In addition, according to the caption control sent from the controller19, the caption converter 14 delays outputting of the received HDcaption data by as much as the time needed for the conversion processingperformed by the converter 16 and then outputs the HD caption data tothe first multiplexer 17-1.

Moreover, according to the caption control sent from the controller 19,the caption converter 14 converts the received HD caption data into SDcaption data, delays outputting of the caption data by as much as thetime needed for the conversion processing performed by the converter 16,and then outputs the SD caption data to the second multiplexer 17-2.

According to a first switching control sent from the controller 19, thefirst switching unit 15-1 switches between outputting, to the firstmultiplexer 17-1, the SD video data supplied from the first buffer 13-1and the HD video data supplied from the second buffer 13-2, or the HDvideo data supplied from the second buffer 13-2 and the SD video datasupplied from the first buffer 13-1.

According to the first switching control sent from the controller 19,the first switching unit 15-1 switches between outputting, to the firstmultiplexer 17-1, the HD video data supplied from the first buffer 13-1and the SD video data supplied from the second buffer 13-2, or the SDvideo data supplied from the second buffer 13-2 and the HD video datasupplied from the first buffer 13-1.

According to a second switching control sent from the controller 19, thesecond switching unit 15-2 switches between outputting, to the converter16, the SD video data supplied from the first buffer 13-1 and the HDvideo data supplied from the second buffer 13-2, or the HD video datasupplied from the second buffer 13-2 and the SD video data supplied fromthe first buffer 13-1.

According to the second switching control sent from the controller 19,the second switching unit 15-2 switches between outputting, to theconverter 16, the HD video data supplied from the first buffer 13-1 andthe SD video data supplied from the second buffer 13-2, or the SD videodata supplied from the second buffer 13-2 and the HD video data suppliedfrom the first buffer 13-1.

When the SD video data are supplied from the second switching unit 15-2,the converter 16 up-converts the supplied SD video data into the HDvideo data according to a conversion control sent from the controller19. The converter 16 outputs the HD video data obtained after theup-conversion to the second multiplexer 17-2. When the HD video data aresupplied from the second switching unit 15-2, the converter 16 downconverts the supplied HD video data into the SD video data according tothe conversion control sent from the controller 19. The converter 16outputs the SD video data obtained after the down-conversion to thesecond multiplexer 17-2.

When SD video data are supplied from the first switching unit 15-1, thefirst multiplexer 17-1 multiplexes the SD caption data supplied from thecaption converter 14 as ancillary data with the supplied SD video data.The first multiplexer 17-1 outputs the SD video data with themultiplexed SD caption data to the first and second output units 18-1,18-2.

When HD video data are supplied from the first switching unit 15-1, thefirst multiplexer 17-1 multiplexes the HD caption data from the captionconverter 14 as the ancillary data with the supplied HD video data. Thefirst multiplexer 17-1 outputs the HD video data multiplexed with the HDcaption data to the first, second output units 18-1, 18-2.

When SD video data are supplied from the converter 16, the secondmultiplexer 17-2 multiplexes the SD caption data supplied from thecaption converter 14 as the ancillary data with the supplied SD videodata. The second multiplexer 17-2 outputs the SD video data multiplexedwith the SD caption data for SD to the first and second output units18-1, 18-2.

When HD video data are supplied from the converter 16, the secondmultiplexer 17-2 multiplexes the HD caption data supplied from thecaption converter 14 as the ancillary data with the supplied HD videodata. The second multiplexer 17-2 outputs the HD video data multiplexedwith the HD caption data to the first and second output units 18-1,18-2.

The first output unit 18-1 is connected to the first output channel.This output channel is preset to output SD video data or HD video data.In this embodiment, the first output channel outputs the HD video data.

When receiving SD video data from the first multiplexer 17-1, the firstoutput unit 18-1 receives the HD video data from the second multiplexer17-2.

When receiving HD video data from the first multiplexer 17-1, the firstoutput unit 18-1 receives the SD video data from the second multiplexer17-2. According to a first output control sent from the controller 19,the first output unit 18-1 switches the connection to output the HDvideo data. In this way, the HD video data are output seamlessly to thefirst output channel.

The second output unit 18-2 is connected to the second output channel.In this embodiment, the second output channel outputs the SD video data.

When receiving HD video data from the first multiplexer 17-1, the secondoutput unit 18-2 receives the SD video data from the second multiplexer17-2.

When receiving the SD video data from the first multiplexer 17-1, thesecond output unit 18-2 receives the HD video data from the secondmultiplexer 17-2. According to a second output control sent from thecontroller 19, the second output unit 18-2 switches the connection tooutput the SD video data. In this way, the SD video data are outputseamlessly to the second output channel.

The controller 19 is equipped with a CPU (central processing unit)including a microprocessor. According to a reproducing control sent fromthe reproducing controller 30, controller 19 reads out the encoded SDdata or the HD encoded data from the storage device 20 and controls thefirst buffer 13-1, the second buffer 13-2, the caption converter 14, thefirst switching unit 15-1, the second switching unit 15-2, the converter16, the first output unit 18-1, and the second output unit 18-2.

In the following example, the processing of the controller 19 when themulti-format output device 10 having the configuration described aboveoutputs HD video data from the first output channel and outputs SD videodata from the second output channel will be described.

FIG. 3 is a flow chart illustrating the processing of the controller 19when the multi-format output device 10 outputs HD video data and SDvideo data. FIG. 3 shows a case, in which the encoded HD data and the SDformat are read out from the storage device 20, the encoded HD data aresupplied from the receiving circuit 11 to the first decoder 12-1, andthe encoded SD data are supplied from the receiving circuit 11 to thesecond decoder 12-2.

FIG. 4 is a diagram illustrating the process of outputting the HD videodata from the first output unit 18-1.

FIG. 5 is a diagram illustrating the process of outputting the SD videodata from the second output unit 18-2.

First, after receiving the reproducing control from the reproducingcontroller 30 (step S31), the controller 19 reads out the encoded HDdata and the encoded SD data stored in the storage device 20 (step S32).

The receiving circuit 11 outputs the encoded HD data to the firstdecoder 12-1 and outputs the encoded SD data to the second decoder 12-2.The first decoder 12-1 decodes the encoded HD data into HD video dataand outputs the HD video data from the first frame to the third frame tothe first buffer 13-1.

The controller 19 issues the first read control to output the HD videodata from the first buffer 13-1 to the second switching unit 15-2 forthe first frame of the HD video data in the first buffer 13-1.

The controller 19 issues the second switch control to output the HDvideo data supplied from the first buffer 13-1 via the second switchingunit 15-2 to the converter 16.

The controller 19 issues a conversion control to start thedown-conversion of the HD video data in the converter 16 (step S33). Theconverter 16 takes two frames for pipeline processing thedown-conversion and outputs SD video data starting from the third frameto the first and second output units 18-1, 18-2.

The controller 19 issues the first read control to output the HD videodata supplied from the first decoder 12-1 to the first switching unit15-1 via the first buffer 13-1 for the third frame.

The controller 19 issues the first switch control to output the HD videodata supplied from the first buffer 13-1 to the first multiplexer 17-1with respect to the first switching unit 15-1.

The controller 19 performs a caption control to output the caption datafor HD supplied from the first decoder 12-1 to the first multiplexer17-1 with respect to the caption converter 14.

The controller 19 performs a caption control to convert the caption datafor HD supplied from the first decoder 12-1 into the caption data for SDand output the caption data to the second multiplexer 17-2 with respectto the caption converter 14.

The controller 19 performs the first output control to output the HDvideo data multiplexed with the caption data for HD supplied from thefirst multiplexer 17-1 with respect to the first output unit 18-1.

The controller 19 performs the second output control to output the SDvideo data multiplexed with the caption data for SD supplied from thesecond multiplexer 17-2 with respect to the second output unit 18-2(step S34).

The second decoder 12-2 decodes the encoded SD data supplied from thereceiving circuit 11 for the 4^(th) frame to the 9^(th) frame into theSD video data and outputs the decoded SD video data to the second buffer13-2.

The controller 19 performs the second read control to output the SDvideo data supplied from the second decoder 12-2 to the second switchingunit 15-2 with respect to the second buffer 13-2 for the 4^(th) frame.

The controller 19 performs the second switch control to output the SDvideo data supplied from the second buffer 13-2 to the converter 16 withrespect to the second switching unit 15-2.

The controller 19 performs conversion control to start the up-conversionof the SD video data supplied from the second switching unit 15-2 withrespect to the converter 16 (step S35). The converter 16 takes twoframes for the up-conversion and outputs the HD video data starting fromthe 6^(th) frame to the first and second output units 18-1, 18-2 afterthe up-conversion.

The controller 19 performs the second read control to output the SDvideo data supplied from the second decoder 12-2 to the first switchingunit 15-1 with respect to the second buffer 13-2 for the 6^(th) frame.

The controller 19 performs the first switch control to output the SDvideo data supplied from the second buffer 13-2 to the first multiplexer17-1 with respect to the first switching unit 15-1.

The controller 19 performs a caption control to output the caption datafor SD supplied from the second decoder 12-2 to the first multiplexer17-1 with respect to the caption converter 14. With respect to thecaption converter 14, the controller 19 converts the caption data for SDsupplied from the second decoder 12-2 into the caption data for HD andperforms a caption control to output the caption data to the secondmultiplexer 17-2.

The controller 19 performs the first output control to output the HDvideo data multiplexed with the caption data for HD supplied from thesecond multiplexer 17-2 with respect to the first output unit 18-1.

The controller 19 performs the second output control to output the SDvideo data multiplexed with the caption data for SD supplied from thefirst multiplexer 17-1 with respect to the second output unit 18-2 (stepS36).

According to the process shown in FIG. 3, the controller 19 canseamlessly connect the HD video data obtained from the encoded HD dataand the HD video data obtained from the encoded SD data between the5^(th) frame and the 6^(th) frame in the first output unit 18-1 (seeFIG. 4). Also, the controller 19 can seamlessly connect the SD videodata obtained from the encoded HD data and the SD video data obtainedfrom the encoded SD data between the 5^(th) frame and the 6^(th) framein the second output unit 18-2.

FIG. 3 shows a case in which the SD video data are output to the secondoutput channel at the same time when the HD video data are output to thefirst output channel. The present invention, however, is not limited tothis. Depending on the reproducing control of the reproducing controller30, the controller 19 can also output the HD video data only to thefirst output channel. Also, depending on the reproducing control of thereproducing controller 30, the controller 19 can also output the SDvideo data only to the second output channel.

As described above, in this embodiment, the controller 19 delays thedata output from the first buffer 13-1 to the first switching unit 15-1by as much as the time needed for the processing in the converter 16compared to the data output from the first buffer 13-1 to the secondswitching unit 15-2. Then, the controller 19 converts the caption datasupplied from the first decoder 12-1 as demanded, delays the captiondata by as much as time needed for the processing in the converter 16,and outputs the caption data to the first and second multiplexers 17-1,17-2. Also, the controller 19 delays the data output from the secondbuffer 13-2 to the first switching unit 15-1 by as much as the timeneeded for the processing in the converter 16 compared to the dataoutput from the second buffer 13-2 to the second switching unit 15-2.Then, the controller 19 controls caption converter 14 to convert thecaption data supplied from the second decoder 12-2 as demanded, delaysthe caption data by as much as the time needed for the processing in theconverter 16, and outputs the caption data to the first and secondmultiplexers 17-1, 17-2. In this way, the multi-format output device 10can eliminate the signal delay caused by the up-conversion anddown-conversion processing, and it is only necessary to convert thecaption data once. Therefore, the complicated control needed in therelated art becomes unnecessary. Even if the multi-format output device10 outputs the SD video data, it is only necessary to convert the SDvideo data once. Therefore, deterioration of the SD video data can bereduced.

Consequently, the multi-format output device disclosed in thisembodiment can output an HD image with caption for an HD and/or SD imagewith caption for SD without undergoing complicated processing andwithout having image quality deterioration.

In the embodiment described above, the case in which the converter 16performs either the up-conversion that converts the SD video data to theHD video data or the down-conversion that converts the HD video data tothe SD video data has been explained. However, the converter 16 can alsoperform a cross conversion that converts first HD video data based on1080i to second HD video data based on 720p or converts the second HD(720p) video data to the first HD (1080i) video data.

For example, in the case of outputting the first HD video data from thefirst output channel and the second HD video data from the second outputchannel, the controller 19 performs the first and second read controlsto delay the output of the video data to the first switching unit 15-1by as much as the time needed for the cross conversion with respect tothe first and second buffers 13-1, 13-2.

Also, the controller 19 performs a caption control to delay the outputof the caption data for the first and second HD video data by as much asthe time needed for the cross conversion with respect to the captionconverter 14.

Also, in this embodiment, the case in which the multi-format outputdevice 10 has the functional configuration shown in FIG. 2 has beenexplained. The multi-format output device, however, can also have otherconfigurations, such as the functional configuration shown in FIG. 6.That is, it is also possible to decode the encoded data by the first andsecond decoders 12-1, 12-2 after the data are first stored in the firstand second buffers 13-1, 13-2.

In this embodiment, the case in which the first and second output units18-1, 18-2 are connected to the first and second output channels,respectively, has been explained. The exemplary embodiment, however, isnot limited to this. For example, the multi-format output device 10 canfurther include a third output unit 18-3 connected to a third outputchannel used for outputting the second HD video data based on 720p.

In each of the embodiments, the case in which the multi-format outputdevice 10 has two sub-systems (that is, two input/output pathways) hasbeen explained. The present disclosure, however, is not limited to this.For example, an exemplary embodiment can include a multi-format outputdevice 10 with more than two sub-systems, such that additionalbuffers/decoders/switches/multiplexers/output units, etc. may beincorporated to accommodate additional input/output formats as desired.

In each of the embodiments, the case in which the multi-format outputdevice 10 has one converter 16 has been explained. The embodiments ofthe present disclosure, however, are not limited to this configuration.For example, the exemplary embodiment can be embodied in the same wayeven if the multi-format output device 10 has two or more converters.

Also, the multi-format output device is not limited use in a videoserver. The embodiments can be applied to any system that requiresmutual conversion and output of video signal in a plurality of formats.

While certain embodiments have been described, these embodiments havebeen presented byway of example only, and are not intended to limit thescope of the inventions. Indeed, the embodiments described herein may beembodied in a variety of other forms; furthermore, various omissions,substitutions and changes in the form of the embodiments describedherein may be made without departing from the spirit of the disclosure.The accompanying claims and their equivalents are intended to cover suchforms or modifications as would fall within the scope and spirit of thedisclosure.

What is claimed is:
 1. A multi-format output device, comprising: areceiving circuit configured to receive a first encoded data and asecond encoded data in a video format different from the first encodeddata and separate and output the first encoded data and the secondencoded data; a first decoder configured to decode the first encodeddata supplied from the receiving circuit to generate a first video dataand a first caption data; a second decoder configured to decode thesecond encoded data supplied from the receiving circuit to generate asecond video data and a second caption data; a conversion unitconfigured to convert the first video data generated by the firstdecoder into a third video data conforming to a same definition as thesecond video data; a buffer configured to hold the second video datagenerated by the second decoder and delay the second video data by atleast a period of time needed for conversion processing in theconversion unit; a caption conversion unit configured to delay thesecond caption data by the period of time to output the second captiondata, convert the first caption data into a third caption dataconforming to the same definition as the second video data, and delaythe third caption data by the period of time to output the third captiondata; a multiplexing unit configured to multiplex the third video datawith the delayed third caption data and multiplex the delayed secondvideo data with the delayed second caption data; and an output unitconfigured to output the third video data multiplexed with the thirdcaption data and the second video data multiplexed with the secondcaption data successively.
 2. The multi-format output device of claim 1,wherein the first video data is a high-definition video data and thesecond video data is a standard definition video data.
 3. Themulti-format output device of claim 1, wherein the first video data is astandard definition video data and the second video data is ahigh-definition video data.
 4. The multi-format output device of claim1, wherein the first video data is a 1080i compliant high-definitionvideo data and the second video data is a 720p compliant high-definitionvideo data.
 5. The multi-format output device of claim 1, wherein thefirst video data is a 720p compliant high-definition video data and thesecond video data is a 1080i compliant high-definition video data.
 6. Amulti-format output device, comprising: a receiving circuit configuredto receive a first encoded data and a second encoded data in a videoformat different from the first encoded data and separate and output thefirst encoded data and the second encoded data; a buffer configured tohold the second encoded data supplied from the receiving circuit anddelay the second encoded data by at least a first period of time; afirst decoder configured to decode the first encoded data supplied fromthe receiving circuit to generate a first video data and a first captiondata; a second decoder configured to decode the second encoded dataoutput from the buffer to generate a second video data and a secondcaption data; a conversion unit configured to convert the first videodata generated by the first decoder into a third video data conformingto a same definition as the second video data for the first period oftime; a caption conversion unit configured to delay the second captiondata by the first period of time to output the second caption data,convert the first caption data into a third caption data conforming tothe same definition as the second video data, and delay the thirdcaption data by the first period of time to output the third captiondata; a multiplexing unit configured to multiplex the third video datawith the delayed third caption data and multiplex the delayed secondvideo data with the delayed second caption data; and an output unitconfigured to output the third video data multiplexed with the thirdcaption data and the second video data multiplexed with the secondcaption data successively.
 7. The multi-format output device of claim 6,wherein the first video data is a high-definition video data and thesecond video data is a standard definition video data.
 8. Themulti-format output device of claim 6, wherein the first video data is astandard definition video data and the second video data is ahigh-definition video data.
 9. The multi-format output device of claim6, wherein the first video data is a 1080i compliant high-definitionvideo data and the second video data is a 720p compliant high-definitionvideo data.
 10. The multi-format output device of claim 6, wherein thefirst video data is a 720p compliant high-definition video data and thesecond video data is a 1080i compliant high-definition video data.
 11. Acontrol method for a multi-format output device, comprising: receiving afirst encoded data and a second encoded data in a video format differentfrom the first encoded data; separating the first encoded data and thesecond encoded data; decoding the separated first encoded data togenerate a first video data and a first caption data; decoding theseparated second encoded data to generate a second video data and asecond caption data; converting the generated first video data into athird video data conforming to a same definition as the second videodata; holding the generated second video data and delaying the secondvideo data by at least a period of time needed for conversionprocessing; delaying the second caption data by the period of time tooutput the second caption data; converting the first caption data into athird caption data conforming to the same definition as the second videodata and delaying the third caption data by the period of time to outputthe data; multiplexing the third video data with the delayed thirdcaption data; multiplexing the delayed second video data with thedelayed second caption data; and outputting the third video datamultiplexed with the third caption data and the second video datamultiplexed with the second caption data successively.